: ♪ ♪ ♪ moving our economy for 160 ♪ ♪ moving our economy for 160 years. bnsf, the engine that connects us. >> and by the bill and melinda gates foundation. dedicated to the idea that all people deserve the chance to live a healthy productive life. >> and with the ongoing support of these institutions and foundations. and... >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: demonstrations, clashes with the police, and tear gas in tahrir square-- familiar scenes in egypt nearly two years ago that led to the fall of longtime leader hosni mubark. but today, they were aimed at egypt's new leader. in the coastal city of alexandria, opponents set fire to the offices of president mohammed morsi's political party, the muslim brotherhood. there and elsewhere in egypt today, the president's critics and supporters clashed in the streets over his decree yesterday exempting himself from judicial review, and giving him authority to take steps against "threats to the revolution." morsi, egypt'